Get roles data from stack output on UC upgrade

Since not all information can be exported from the
stacks, the intent is to backport the depends-on
to the release intended as the upgrade from release.
i.e the depends on need to go back to Train.

The alternative is to require the user to provide the
roles_data file for each overcloud stack managed by
the undercloud being upgraded as input to the upgrade
command. Support for this is provided in the previous
patch in this chain.

Depends-On: https://review.opendev.org/791476
Related: blueprint network-data-v2-ports
Change-Id: Icc6a7a438e9d0f39d003d1cf8ed84d6fb1d5485a

scripts/undercloud-upgrade-ephemeral-heat.py

@@ -21,6 +21,7 @@ import logging
 import os
 import subprocess
 import tarfile
+import tempfile
 import time
 import yaml
 
@@ -161,25 +162,43 @@ def _log_and_raise(msg):
     raise Exception(msg)
 
 
-def _get_role_data_file(stack):
+def _get_role_data_file(heat, stack, fd, temp_file_path):
     """Get the role data file for a stack
 
+    :param heat: Heat client
+    :type heat: heatclient.client.Client
     :param stack: Stack name to query for passwords
     :type stack: str
+    :fd: File descriptor
+    :type fd: int
+    :temp_file_path: Path to role data temp file
+    :type temp_file_path: str
     :return: Path to the role data file
     :rtype:: str
     """
-    if not os.path.isfile(ROLE_DATA_MAP_FILE):
-        _log_and_raise("Overcloud stack role data mapping file: {} was not "
-                       "found.".format(ROLE_DATA_MAP_FILE))
+    try:
+        _stack = heat.get_stack(stack)
+        stack_outputs = {i['output_key']: i['output_value']
+                         for i in _stack.outputs}
+        roles_data = stack_outputs[
+            'TripleoHeatTemplatesJinja2RenderingDataSources']['roles_data']
 
-    with open(ROLE_DATA_MAP_FILE, 'r') as f:
-        data = yaml.safe_load(f.read())
+        with os.fdopen(fd, 'w') as tmp:
+            tmp.write(yaml.safe_dump(roles_data))
 
-    roles_data_file = data.get(stack)
-    if not roles_data_file or not os.path.isfile(roles_data_file):
-        _log_and_raise("Roles data file: {} for stack {} not found."
-                       .format(roles_data_file, stack))
+        roles_data_file = temp_file_path
+    except KeyError:
+        if not os.path.isfile(ROLE_DATA_MAP_FILE):
+            _log_and_raise("Overcloud stack role data mapping file: {} was "
+                           "not found.".format(ROLE_DATA_MAP_FILE))
+
+        with open(ROLE_DATA_MAP_FILE, 'r') as f:
+            data = yaml.safe_load(f.read())
+
+        roles_data_file = data.get(stack)
+        if not roles_data_file or not os.path.isfile(roles_data_file):
+            _log_and_raise("Roles data file: {} for stack {} not found."
+                           .format(roles_data_file, stack))
 
     return roles_data_file
 
@@ -278,10 +297,12 @@ def export_network_virtual_ips(stack, stack_dir):
     os.chmod(vip_data_path, 0o600)
 
 
-def export_provisioned_nodes(stack, stack_dir):
+def export_provisioned_nodes(heat, stack, stack_dir):
     """Export provisioned nodes from an existing stack and write baremetal
     deployment definition file.
 
+    :param cloud: Heat client
+    :type cloud: heatclient.client.Client
     :param stack: Stack name to query for networks
     :type stack: str
     :param stack_dir: Directory to save the generated data file
@@ -290,16 +311,20 @@ def export_provisioned_nodes(stack, stack_dir):
     :return: None
     :rtype: None
     """
-    roles_data_file = _get_role_data_file(stack)
-    bm_deployment_path = os.path.join(
-        stack_dir, "tripleo-{}-baremetal-deployment.yaml".format(stack))
-    LOG.info("Exporting provisioned nodes from stack %s to %s"
-             % (stack, bm_deployment_path))
-    subprocess.check_call(['openstack', 'overcloud', 'node', 'extract',
-                           'provisioned', '--stack', stack, '--roles-file',
-                           roles_data_file, '--output', bm_deployment_path,
-                           '--yes'])
-    os.chmod(bm_deployment_path, 0o600)
+    fd, temp_file_path = tempfile.mkstemp()
+    try:
+        roles_data_file = _get_role_data_file(heat, stack, fd, temp_file_path)
+        bm_deployment_path = os.path.join(
+            stack_dir, "tripleo-{}-baremetal-deployment.yaml".format(stack))
+        LOG.info("Exporting provisioned nodes from stack %s to %s"
+                 % (stack, bm_deployment_path))
+        subprocess.check_call(['openstack', 'overcloud', 'node', 'extract',
+                               'provisioned', '--stack', stack, '--roles-file',
+                               roles_data_file, '--output',
+                               bm_deployment_path, '--yes'])
+        os.chmod(bm_deployment_path, 0o600)
+    finally:
+        os.remove(temp_file_path)
 
 
 def main():
@@ -347,7 +372,7 @@ def main():
         stack_dir = os.path.join(working_dir, stack)
         export_networks(stack, stack_dir)
         export_network_virtual_ips(stack, stack_dir)
-        export_provisioned_nodes(stack, stack_dir)
+        export_provisioned_nodes(heat, stack, stack_dir)
 
     if database_exists():
         backup_dir = os.path.join(